Bathtub apparatus

Abstract

To reduce a probability of failure occurrence leading to a serious accident to as close to zero as possible in a bathtub apparatus equipped with an electrocardiographic signal detection function.SOLUTION: A bathtub apparatus (1) equipped with an electrocardiographic signal detection function includes: a bathtub body (2); a positive electrode (4b) and a negative electrode (4a) provided in the bathtub body for detecting an electrocardiographic signal of a bather bathing in the bathtub body through hot water stored in the bathtub body; an electrocardiographic signal acquisition part (6) for acquiring the electrocardiographic signal of the bather on the basis of a potential difference between the positive electrode and the negative electrode; a power supply part (10) for supplying power to the electrocardiographic signal acquisition part; a power source part (12) connected to a commercial power source for supplying power to the power supply part; and a power source control part (14) for controlling supply and stop of power from the power source part to the power supply part. The power source part supplies power to the power supply part through an isolation transformer (13), and the isolation transformer is provided with a contact prevention plate (13d).SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a bathtub apparatus, and more particularly to a bathtub apparatus having a function for detecting electrocardiogram signals. [Background technology]

[0002] JP 2022-16063 A (Patent Document 1) describes a bathtub device. In this bathtub device, a set of electrodes is provided on the inner wall surface of the bathtub body, and these electrodes detect the bather's electrocardiogram signal. That is, the bather's electrocardiogram signal in the bathtub body is obtained by detecting the potential difference that appears between these electrodes through the hot and cold water stored in the bathtub body. Here, the signal of the potential difference that appears between the electrodes is processed by an amplifier circuit and a filter circuit and then obtained as an electrocardiogram signal. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-16063 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the invention described in Patent Document 1, if the power source for operating the amplifier circuit that inputs the signal of the potential difference appearing between the electrodes is obtained directly from a commercial power source, there is a possibility that the voltage of the commercial power source will be applied to the electrodes installed on the inner wall surface of the bathtub body due to a malfunction of the device. Such a malfunction will only occur if multiple circuit components that obtain power from the commercial power source malfunction at the same time, and although the probability of this occurring is extremely low, if it does occur, it could lead to a serious accident. For this reason, the probability of such an accident occurring needs to be kept as close to zero as possible.

[0005] Therefore, an object of the present invention is to reduce the probability of occurrence of a malfunction that could lead to a serious accident as close to zero as possible in a bathtub apparatus equipped with an electrocardiogram signal detection function. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, the present invention provides a bathtub apparatus equipped with an electrocardiac signal detection function, comprising a bathtub body for storing hot and cold water, a positive electrode and a negative electrode provided in the bathtub body for detecting the electrocardiac signal of a bather bathing in the bathtub body through the hot and cold water stored in the bathtub body, an electrocardiac signal acquisition unit for acquiring the electrocardiac signal of the bather based on the potential difference between the positive and negative electrodes, a power supply unit for supplying power to the electrocardiac signal acquisition unit, a power supply unit connected to a commercial power source and supplying power to the power supply unit, and a power supply control unit for controlling the supply and stop of power from the power supply unit to the power supply unit, wherein the power supply unit supplies power to the power supply unit via an isolation transformer, and the isolation transformer is equipped with a contact prevention plate.

[0007] According to the present invention configured as described above, the power supply unit supplies power to the power supply unit through an insulating transformer, and the insulating transformer is equipped with a contact prevention plate, so that even if the insulation in the insulating transformer is broken, the current supplied from the commercial power supply flows to the earth through the contact prevention plate, thereby making it possible to extremely increase safety. As a result, in a bathtub device equipped with an electrocardiogram detection function, the probability of occurrence of a malfunction that could lead to a serious accident can be reduced to as close to zero as possible.

[0008] In the present invention, preferably, the device further includes a signal transmitting unit that transmits a signal to the power supply control unit, and the signal transmitting unit transmits a signal based on the potential difference between the positive electrode and the negative electrode acquired by the electrocardiogram signal acquiring unit to the power supply control unit, and the power supply control unit continues or stops the transmission of power from the power supply unit to the power supply unit based on the transmitted signal.

[0009] According to the present invention configured in this way, a signal indicating whether or not operation should be continued is sent to the power supply control unit as a result of signal processing by the microcomputer based on the potential difference between the positive and negative electrodes, and the transmission of power from the power supply unit to the power supply unit is continued or stopped based on the transmitted signal. Therefore, if an abnormality occurs in the operation of the bathtub device, the transmission of power to the power supply unit can be stopped early, further reducing the probability of accidents caused by malfunctions. In addition, since the transmission of power is continued or stopped based on the signal detected by the positive and negative electrodes provided on the bathtub body to detect electrocardiogram signals, the occurrence of an abnormality can be detected without providing a special sensor.

[0010] In the present invention, the power supply control section preferably stops transmission of power from the power supply section to the power supply section at least temporarily when an uncertain potential signal is detected by the electrocardiogram signal acquisition section.

[0011] When the positive and negative electrodes provided on the bathtub body are not submerged in the hot and cold water stored in the bathtub body, and when the conductor connected to the positive or negative electrodes is disconnected, the potential difference between the positive and negative electrodes becomes indefinite. According to the present invention configured as described above, when an indefinite potential signal is detected by the electrocardiogram signal acquisition unit, the transmission of power from the power supply unit to the power supply unit is at least temporarily stopped. This makes it possible to prevent power from being transmitted to the power supply unit when there is an abnormality in the bathtub device or when there is not enough hot and cold water stored in the bathtub body, thereby further reducing the probability of accidents occurring and avoiding the transmission of unnecessary power.

[0012] In the present invention, preferably, when hot water is stored in the bathtub body but the electrocardiogram signal acquisition unit detects that no bather is present in the bathtub body, the power supply control unit continues to transmit power from the power supply unit to the power supply unit.

[0013] When hot water is stored in the bathtub body but no bather is inside, the potential difference between the positive and negative electrodes remains at approximately zero. According to the present invention configured as described above, when hot water is stored in the bathtub body but no bather is detected inside the bathtub body, the power supply unit continues to transmit power to the power supply unit. Therefore, the electrocardiogram signal acquisition unit operates normally, and can immediately start acquiring electrocardiogram signals when a bather enters the bathtub body.

[0014] In the present invention, preferably, the power supply control unit continues transmitting power from the power supply unit to the power supply unit when hot water is stored in the bathtub body and the electrocardiogram signal acquisition unit detects that a bather is present in the bathtub body.

[0015] When hot water is stored in the bathtub body and a person is bathing inside, the bather's electrocardiogram signal appears as a potential difference between the positive and negative electrodes. According to the present invention configured as described above, when hot water is stored in the bathtub body and it is detected that a person is bathing inside the bathtub body, the transmission of power from the power supply unit continues. This allows the bathtub device to safely obtain an electrocardiogram signal while it is operating normally, and this can be used to provide information about bathing to the bather and to monitor the bather.

[0016] In the present invention, preferably, the power supply control unit stops transmitting power to the power supply unit when the state changes from one in which the electrocardiogram signal acquiring unit detects the presence of a bather in the bathtub body to one in which the electrocardiogram signal acquiring unit detects an uncertain potential signal.

[0017] When a bather leaves the bathtub body, the bather's electrocardiogram signal is usually detected, but the potential difference between the positive and negative electrodes is almost zero. Therefore, in normal operation of the bathtub device, the bathtub device does not change from a state in which an electrocardiogram signal is detected to a state in which an indeterminate potential signal is detected. According to the present invention configured as described above, in such a case, the transmission of power to the power supply unit is stopped, so that an abnormality in the bathtub device can be quickly detected and the transmission of power can be stopped. This further reduces the probability of an accident and prevents unnecessary power transmission. Effect of the Invention

[0018] According to the present invention, in a bathtub apparatus equipped with an electrocardiogram signal detection function, the probability of occurrence of a malfunction that could lead to a serious accident can be reduced to as close to zero as possible. [Brief description of the drawings]

[0019] [Figure 1] 1 is a perspective view showing an entire bathroom in which a bathtub apparatus according to an embodiment of the present invention is installed. [Diagram 2] 1 is a perspective view of a bathtub apparatus according to an embodiment of the present invention, viewed obliquely from above. [Diagram 3] 1 is a block diagram showing an outline of an electrical system of a bathtub apparatus according to an embodiment of the present invention. [Figure 4] 1 is a block diagram showing a schematic configuration of an electrocardiogram signal acquisition unit provided in a bathtub apparatus according to an embodiment of the present invention. [Diagram 5] 2 is a schematic diagram showing the configuration of a power supply unit in a bathtub apparatus according to an embodiment of the present invention. FIG. [Figure 6] 1 is a diagram showing an example of a bathing person signal waveform acquired by an electrocardiogram signal acquisition unit in a bathtub apparatus according to an embodiment of the present invention. FIG. [Figure 7] A figure showing an example of a no-bather signal waveform acquired by an electrocardiogram signal acquisition unit when the water level is above a specified level in a bathtub apparatus according to an embodiment of the present invention. [Figure 8]13 is a diagram showing an example of an indeterminate potential signal waveform acquired by an electrocardiogram signal acquisition unit when the specified water level is not reached in a bathtub apparatus according to an embodiment of the present invention. FIG. [Figure 9] 4 is a flowchart showing the operation of a bathtub apparatus according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Next, a bathtub apparatus according to an embodiment of the present invention will be described with reference to the accompanying drawings. Fig. 1 is a perspective view showing an entire bathroom in which a bathtub apparatus according to an embodiment of the present invention is installed. Fig. 2 is a perspective view of the bathtub apparatus according to an embodiment of the present invention, seen obliquely from above. Fig. 3 is a block diagram showing an outline of the electrical system of the bathtub apparatus according to an embodiment of the present invention.

[0021] As shown in Fig. 1, a bathtub apparatus 1 according to an embodiment of the present invention comprises a bathtub main body 2, a negative electrode 4a, a positive electrode 4b, and a reference electrode 4c attached to the bathtub main body 2, an electrocardiogram signal acquisition unit 6 that processes signals acquired by the electrodes, and a water discharge device 8 provided on the upper edge of the bathtub main body 2, and is installed in a bathroom R. A remote control 6a is also attached to the wall of the bathroom R, and this remote control 6a can be used to operate the bathtub apparatus 1's electrocardiogram signal display function and the water discharge device 8. Furthermore, in this embodiment, the bathtub apparatus 1 is placed on one side of the bathroom R so as to be in contact with the wall.

[0022] The bathtub body 2 is formed in a roughly rectangular box shape in a plan view, and is configured to store hot and cold water inside. In this embodiment, the bathtub body 2 is positioned so that one of its long sides and the entire two short sides on either side of it are in contact with the inner wall surface of the bathroom R. The inner wall surface constituting one of the short sides of the bathtub body 2 is configured as a backrest surface 2a, which is a first inner wall surface formed so that a bather can lean against it. Here, the backrest surface refers to the inner wall surface that the bather's back comes in contact with when bathing.

[0023] The water discharge device 8 is provided on the upper part of the backrest surface 2a of the bathtub body 2, and is configured to discharge hot water toward the inside of the bathtub body 2. As shown in Fig. 2, in this embodiment, the water discharge device 8 has a flat, wide water outlet 8a that extends along the upper edge of the backrest surface 2a, and is configured to discharge hot water toward the shoulders of the bather leaning against the backrest surface 2a.

[0024] As shown in FIG. 2, the negative electrode 4a and the positive electrode 4b are a pair of electrodes attached to the bathtub body 2 in order to detect the bather's electrocardiogram signal via the hot and cold water stored in the bathtub body 2. The bather's electrocardiogram signal is obtained as a signal of the potential difference between the negative electrode 4a and the positive electrode 4b. The pair of electrodes consisting of the negative electrode 4a and the positive electrode 4b are both arranged on the backrest surface 2a that constitutes the short side of the bathtub body 2. The reference electrode 4c is an electrode for obtaining a reference potential of the potential detected by the negative electrode 4a and the positive electrode 4b, and this electrode is also arranged on the backrest surface 2a of the bathtub body 2. The reference electrode 4c may be omitted.

[0025] The electrocardiogram signal acquiring unit 6 is electrically connected to the negative electrode 4a, the positive electrode 4b, and the reference electrode 4c, and is configured to acquire the electrocardiogram signal of the bather based on the potential difference between the positive electrode 4b and the negative electrode 4a. In this embodiment, the electrocardiogram signal acquiring unit 6 is configured to detect the bather's heart rate based on the acquired electrocardiogram signal and display it on the display (not shown) of the remote control 6a. This allows the bather to check his / her own health condition and how warm his / her body is. The present invention can also be configured to transmit the information acquired by the electrocardiogram signal acquiring unit 6 to an external wireless communication device (not shown) so that the bather's condition can be monitored from outside the bathroom.

[0026] Next, with reference to FIG. 3, a power supply system in the bathtub apparatus 1 according to the embodiment of the present invention will be described. As shown in Figure 3, the bathtub equipment 1 includes a power supply unit 10 that supplies power to the electrocardiogram signal acquisition unit 6, a power supply unit 12 that is connected to a commercial power source and supplies power to the power supply unit 10, an isolation transformer 13 connected between the power supply unit 12 and the power supply unit 10, a power supply control unit 14 that controls the power supply unit 12, and a signal transmission unit 16 that transmits signals to the power supply control unit 14.

[0027] The power supply unit 10 is electrically connected to the electrocardiogram signal acquisition unit 6 and configured to supply power for operating the electrocardiogram signal acquisition unit 6 to the electrocardiogram signal acquisition unit 6. The power supply unit 10 is also electrically connected to the signal transmission unit 16 and configured to supply power for operating the electrocardiogram signal acquisition unit 6 to the signal transmission unit 16. That is, in this embodiment, the electrocardiogram signal acquisition unit 6 and the signal transmission unit 16 are operated by power supplied from the power supply unit 10. On the other hand, the power supply unit 10 is insulated from a commercial power source, and is configured to receive power from the power supply unit 12 via an insulating transformer 13 and supply the supplied power to the electrocardiogram signal acquisition unit 6 and the signal transmission unit 16. A specific configuration of the power supply unit 10 will be described later.

[0028] The signal transmitting unit 16 is configured to transmit a signal to the power supply control unit 14 in an electrically insulated state. That is, the signal transmitting unit 16 is configured to transmit a control signal to the power supply control unit 14 based on a signal of the potential difference between the positive electrode 4b and the negative electrode 4a acquired by the electrocardiogram signal acquiring unit 6. As described above, the power for operating the signal transmitting unit 16 is supplied from the electrically connected power supply unit 10, while the control signal from the signal transmitting unit 16 to the power supply control unit 14 is transmitted in an electrically insulated state. In this embodiment, the control signal is transmitted from the signal transmitting unit 16 to the power supply control unit 14 via a photocoupler (not shown). Note that the control signal can also be transmitted from the signal transmitting unit 16 to the power supply control unit 14 wirelessly using radio waves.

[0029] The power supply unit 12 is connected to a commercial power source 18 and configured to supply AC power to the insulating transformer 13 via an earth leakage breaker (ELB) 12a. That is, the power supply unit 12 is configured to supply power to the power supply unit 10 via the insulating transformer 13. Therefore, even if the electric components constituting the power supply unit 10 and the power supply unit 12 fail, the voltage (100V) of the commercial power source 18 connected to the power supply unit 12 is not directly applied to the power supply unit 10. Therefore, although the electrocardiogram signal acquisition unit 6, the signal transmission unit 16, the negative electrode 4a, the positive electrode 4b, and the reference electrode 4c are electrically connected to the power supply unit 10, the voltage of the commercial power source 18 is not directly applied to these.

[0030] The isolation transformer 13 has a primary winding 13a connected to the power supply unit 12, a secondary winding 13b connected to the power supply unit 10, a core 13c that transmits magnetic flux from the primary winding 13a to the secondary winding 13b by electromagnetic induction, and a contact prevention plate 13d provided between the primary winding 13a and the secondary winding 13b.

[0031] The primary winding 13a is a high-voltage coil connected to the power supply unit 12, and is applied with a high AC voltage from a commercial power supply 18. The core 13c is an iron core that transmits an alternating magnetic flux generated by application of an AC voltage to the primary winding 13a to the secondary winding 13b. The secondary winding 13b is a low-voltage coil connected to the power supply unit 10, and is configured to generate an AC electromotive force lower than the AC voltage applied to the primary winding 13a based on the magnetic flux transmitted by the core 13c. In the insulating transformer 13, the primary winding 13a and the secondary winding 13b are electrically insulated from each other, and no current flows directly from the primary winding 13a to the secondary winding 13b.

[0032] The contact prevention plate 13d is a metal plate disposed between the primary winding 13a and the secondary winding 13b. The contact prevention plate 13d is connected to the earth via a grounding wire. Preferably, the grounding of the contact prevention plate 13d is a type D grounding, and the contact prevention plate 13d is connected to the earth so that the grounding resistance value is 100Ω or less. For example, the contact prevention plate 13d is connected to the earth so that the electrical resistance between the contact prevention plate 13d and a grounding wire (not shown) extending from a grounding electrode provided on a utility pole is 100Ω or less.

[0033] In this way, by providing contact prevention plate 13d on insulating transformer 13 and connecting it to earth, even if the insulation of primary winding 13a is broken down, the current supplied from commercial power source 18 flows to earth and no high voltage is generated in secondary winding 13b. This ensures the safety of users of bathtub equipment 1.

[0034] The power supply control unit 14 is connected to the power supply unit 12 and is configured to control the supply and stop of power from the power supply unit 12 to the power supply unit 10. That is, the signal transmission unit 16 transmits a control signal to the power supply control unit 14, and the supply and stop of power from the power supply unit 12 to the power supply unit 10 (insulation transformer 13) is controlled based on this control signal. In this embodiment, power for operating the power supply control unit 14 is supplied from the electrically connected power supply unit 12, while the transmission of a control signal from the signal transmission unit 16 to the power supply control unit 14 is performed in an electrically insulated state via a photocoupler (not shown). Thus, in this embodiment, the right and left sides of the dashed line shown in the block diagram of FIG. 3 are electrically insulated, and even if a failure occurs in a component, the voltage of the commercial power supply 18 is not directly applied to the area to the right of the dashed line.

[0035] Next, the configuration of the electrocardiogram signal acquiring unit 6 will be described with reference to FIG. FIG. 4 is a block diagram showing a schematic configuration of the electrocardiogram signal acquiring unit 6. As shown in FIG.

[0036] The electrocardiogram signal acquisition unit 6 is an electric circuit to which the negative electrode 4a, the positive electrode 4b, and the reference electrode 4c are connected, and is disposed on the rear side of the backrest surface 2a of the bathtub body 2. The signals acquired by the negative electrode 4a, the positive electrode 4b, and the reference electrode 4c are processed by the electrocardiogram signal acquisition unit 6, and the processing results are displayed on a remote control 6a disposed in the bathroom R and / or a display device (not shown) disposed outside the bathroom R.

[0037] 4, the electrocardiogram signal acquiring unit 6 includes a differential amplifier circuit 26, a filter circuit 28, an amplifier circuit 30, an A / D converter 32, a discrimination circuit 34, and a heart rate conversion unit 36c. As described above, the power for operating these circuits is supplied from the power supply unit 10. The differential amplifier circuit 26 is an amplifier circuit to which the conductors extending from the negative electrode 4a and the positive electrode 4b are connected, and is configured to amplify the differential voltage between the negative electrode 4a and the positive electrode 4b.

[0038] The filter circuit 28 is configured to receive the differential voltage amplified by the differential amplifier circuit 26, remove unnecessary frequency band components such as hum, and pass signal components in a required frequency band. The amplifier circuit 30 is configured to amplify a signal from which unnecessary frequency band components such as hum have been removed by the filter circuit 28. A conductor (not shown) extending from the reference electrode 4c is connected to the differential amplifier circuit 26, the filter circuit 28, and the ground of the amplifier circuit 30.

[0039] The A / D converter 32 is configured to convert the analog signal amplified by the amplifier circuit 30 into a digital signal. The determination circuit 34 is configured to receive the digital signal that has been A / D converted by the A / D converter 32, and to determine the input signal waveform based on the input digital signal.

[0040] The digital signal A / D converted by the A / D converter 32 is sent to a heart rate conversion section 36c of the signal transmission section 16, which calculates the bather's heart rate and transmits the result to the remote control 6a or the like in a non-contact manner. In this embodiment, the signal transmission section 16 transmits the digital signal to the remote control 6a by wireless communication using Bluetooth (registered trademark). In this embodiment, the signal transmission section 16 also transmits the result of the determination made by the determination circuit 34 to the power supply control section 14 in an electrically insulated state. The determination made by the determination circuit 34 will be described later.

[0041] The remote control 6a has built-in recording unit 36a, display unit 36b, etc. The signal sent from the electrocardiogram signal acquisition unit 6 is recorded in recording unit 36a, and the electrocardiogram waveform and heart rate of the bather are displayed as graphs on display unit 36b. The electrocardiogram waveform and the bather's heart rate can also be displayed on a display device (not shown) outside bathroom R, allowing the bather's health condition to be monitored from outside bathroom R.

[0042] Next, the configuration of the power supply unit 10 will be described with reference to FIG. FIG. 5 is a schematic diagram showing the configuration of the power supply unit.

[0043] 5, a commercial power supply 18 is connected to power supply unit 12, and power supply unit 12 applies a voltage of 100 V AC supplied from commercial power supply 18 to isolation transformer 13. Isolation transformer 13 steps down the voltage applied from power supply unit 12 and supplies it to power supply unit 10.

[0044] The power supply unit 10 includes a pre-rectifier circuit 10a, a pulse generating circuit 10b, a transformer 10c, and a post-rectifier circuit 10d. The insulating transformer 13 steps down the applied AC voltage and supplies it to the pre-rectifier circuit 10a. The pre-rectifier circuit 10a is composed of a rectifier diode, a smoothing capacitor (not shown), etc. In this embodiment, the pre-rectifier circuit 10a is configured to convert the AC voltage supplied from the insulating transformer 13 into 24V DC.

[0045] The pulse generating circuit 10b is configured to convert the DC voltage supplied from the pre-rectifier circuit 10a into a pulse of a predetermined frequency and output it to the transformer 10c. The pulse generating circuit 10b is configured with a FET (Field Effect Transistor) (not shown) that switches and converts the DC voltage supplied from the pre-rectifier circuit 10a into a pulsed voltage waveform.

[0046] The transformer 10c is configured to step down the pulse waveform supplied from the pulse generating circuit 10b to generate a predetermined AC voltage. The transformer 10c is composed of a primary winding, a core, a secondary winding (not shown), etc., and is configured to step down the input pulse voltage at a predetermined ratio. The frequency of the pulse waveform generated by the pulse generating circuit 10b is set to a frequency that allows efficient voltage conversion by the transformer 10c.

[0047] The post-stage rectifier circuit 10d is composed of a rectifier diode, a smoothing capacitor (not shown), etc. In this embodiment, the post-stage rectifier circuit 10d is configured to convert the AC voltage supplied from the transformer 10c into DC 5V. The DC 5V voltage thus obtained is supplied to the electrocardiogram signal acquisition unit 6 and the signal transmission unit 16.

[0048] Next, the signal waveforms acquired by the electrocardiogram signal acquiring section 6 will be described with reference to FIGS. 6 to 8 are diagrams showing examples of signal waveforms acquired by the electrocardiogram signal acquiring unit 6. FIG.

[0049] FIG. 6 shows an example of a voltage waveform acquired by the electrocardiogram signal acquisition unit 6 when hot water is stored in the bathtub body 2 up to a water level higher than the position where the negative electrode 4a and the positive electrode 4b are provided and a bather is in the bathtub body 2. In this case, as shown in FIG. 6, the electrocardiogram waveform of the bather is acquired by the electrocardiogram signal acquisition unit 6 as a signal of the potential difference between the negative electrode 4a and the positive electrode 4b via the hot water stored in the bathtub body 2. In this embodiment, the heart rate conversion unit 36c (FIG. 4) built into the signal transmission unit 16 detects the bather's heart rate based on this electrocardiogram waveform. In this specification, a signal of the type shown in FIG. 6 detected when a bather is in the bathtub body 2 is called a "bathing person signal."

[0050] FIG. 7 shows an example of a waveform acquired by the electrocardiogram signal acquisition unit 6 when hot water is stored in the bathtub body 2 up to a water level higher than the positions where the negative electrode 4a and the positive electrode 4b are provided, but no bather is in the bathtub body 2. In this state, both the negative electrode 4a and the positive electrode 4b are in contact with the hot water in the bathtub body 2, and the potential difference between the negative electrode 4a and the positive electrode 4b is almost zero. Therefore, in this case, a voltage waveform in which the voltage remains almost zero as shown in FIG. 7 is acquired by the electrocardiogram signal acquisition unit 6. In this specification, a signal of the type shown in FIG. 7 that is detected when no bather is in the bathtub body 2 is referred to as a "no-bather signal."

[0051] FIG. 8 shows an example of a waveform acquired by the electrocardiogram signal acquisition unit 6 when hot water is not stored in the bathtub body 2 or when the water level is lower than the position where the negative electrode 4a and the positive electrode 4b are provided even if hot water is stored in the bathtub body 2. In such a state, the potential of the negative electrode 4a and the positive electrode 4b becomes unstable (float state), the potential difference between the negative electrode 4a and the positive electrode 4b also becomes unstable, and the waveform fluctuates drastically. Therefore, in such a state, the waveform acquired by the electrocardiogram signal acquisition unit 6 becomes a random noise waveform. In addition, even if hot water is stored in the bathtub body 2, the potential difference between the negative electrode 4a and the positive electrode 4b may become unstable if a failure such as a breakage of the conductor (not shown) connected to the negative electrode 4a or the positive electrode 4b occurs. In this specification, a signal of the type shown in FIG. 8 detected when the potential difference between the negative electrode 4a and the positive electrode 4b is unstable is called an "undefined potential signal."

[0052] A discrimination circuit 34 (FIG. 4) built into the electrocardiogram signal acquiring unit 6 discriminates whether the waveform of the potential difference between the negative electrode 4a and the positive electrode 4b acquired by the electrocardiogram signal acquiring unit 6 corresponds to a "bather signal", a "non-bather signal", or a "potential-undefined signal". The discrimination result by this discrimination circuit 34 is transmitted to the power supply control unit 14 by the signal transmitting unit 16. That is, the signal transmitting unit 16 transmits a signal based on the potential difference between the positive electrode 4b and the negative electrode 4a acquired by the electrocardiogram signal acquiring unit 6 to the power supply control unit 14. As will be described later, the power supply control unit 14 continues or stops the transmission of power from the power supply unit 12 to the power supply unit 10 based on the signal transmitted from the signal transmitting unit 16.

[0053] Next, the operation of the bathtub apparatus 1 according to the embodiment of the present invention will be described with reference to FIG. Fig. 9 is a flowchart showing the operation of the bathtub apparatus 1 of this embodiment. When the "Auto" button on the remote control is pressed in the bathtub apparatus 1 of this embodiment, the process of the flowchart shown in Fig. 9 is executed. That is, in the bathtub apparatus 1 of this embodiment, when the "Auto" button (not shown) on the remote control 6a in the bathroom R or on a remote control (not shown) outside the bathroom R is pressed, the bathtub is filled with water if there is no water stored in the bathtub main body 2, and the water in the bathtub main body 2 is heated (reheated) to a set temperature if there is water stored.

[0054] 9, power transmission is started from the power supply unit 12 to the power supply unit 10. This starts power supply to the electrocardiogram signal acquisition unit 6. Next, in step S2, it is determined whether or not the bathtub body 2 is in a state before the water has been filled (a state in which hot and cold water has not yet been stored in the bathtub body 2 up to a predetermined water level). Note that the bathtub apparatus 1 of this embodiment is equipped with a water level gauge (not shown) that measures the water level in the bathtub body 2, and whether or not the water has not been filled is determined based on the detection value of this water level gauge. If the water has not been filled, the process proceeds to step S3, and if filling of the water has been completed, the process proceeds to step S5.

[0055] In step S3, filling of the bathtub body 2 with hot water begins. That is, hot water is supplied into the bathtub body 2 from a water heater (not shown). Thereafter, when a predetermined amount of hot water at a predetermined temperature is supplied from a water heater (not shown) into the bathtub body 2, filling the bathtub body 2 with hot water is completed in step S4.

[0056] Next, in step S5, it is determined whether or not the bathtub body 2 is filled with hot water up to a predetermined water level. In step S5, first, the signal waveform of the potential difference between the positive electrode 4b and the negative electrode 4a acquired by the electrocardiogram signal acquisition unit 6 is discriminated by the discrimination circuit 34 of the electrocardiogram signal acquisition unit 6. If the acquired signal waveform is a "person taking a bath" or a "person not taking a bath" signal, it is determined that the water level is higher than the height at which the positive electrode 4b and the negative electrode 4a are provided, and the process in the flowchart proceeds to step S6.

[0057] On the other hand, if the signal waveform acquired by the electrocardiogram signal acquisition unit 6 is an "undefined potential signal," the process proceeds to step S10, where it is determined that an abnormality has occurred. That is, the detection of the "undefined potential signal" waveform indicates that the water level in the bathtub body 2 is lower than the height of the positive electrode 4b and the negative electrode 4a, even though a predetermined amount of hot water has been supplied to the bathtub body 2 in step S4. This may be caused by the plug (not shown) of the bathtub body 2 being open, and hot water not being stored in the bathtub body 2 even after it has been supplied. Alternatively, it may be that there is some kind of malfunction in the signal system that detects the potential difference between the positive electrode 4b and the negative electrode 4a. For this reason, the electrocardiogram signal acquisition unit 6 sends a signal to the remote control 6a in the bathroom R and a remote control (not shown) outside the bathroom R, and displays the occurrence of an abnormality on the remote control to notify the user.

[0058] Furthermore, in step S11, the signal transmission unit 16 sends a signal to the power supply control unit 14 to stop the transmission of power from the power supply unit 12 to the power supply unit 10, and ends one round of processing of the flowchart shown in FIG. 9. In this embodiment, the signal transmission unit 16 sends a signal to the power supply control unit 14 to activate the earth leakage breaker 12a provided in the power supply unit 12, thereby stopping the transmission of power from the power supply unit 12 to the power supply unit 10. In this way, the signal transmission unit 16 transmits a signal based on the potential difference between the positive electrode 4b and the negative electrode 4a acquired by the electrocardiogram signal acquisition unit 6 to the power supply control unit 14. Meanwhile, the power supply control unit 14 stops the transmission of power from the power supply unit 12 to the power supply unit 10 based on the transmitted signal. This makes it possible to avoid the supply of power to the electrocardiogram signal acquisition unit 6 in a state in which an electrocardiogram signal cannot be detected or in a state in which a malfunction occurs, and prevents the waste of power or the occurrence of an accident.

[0059] In this embodiment, the discrimination circuit 34 discriminates whether the waveform acquired by the electrocardiogram signal acquisition unit 6 corresponds to a "bathing person signal", a "non-bathing person signal", or an "undefined potential signal", and a control signal indicating the discrimination result is transmitted from the signal transmission unit 16 to the power supply control unit 14. The power supply control unit 14 determines whether to transmit or stop power from the power supply unit 12 to the insulating transformer 13 and the power supply unit 10 based on the received control signal. In contrast, as a modified example, the present invention can be configured so that the signal transmission unit 16 determines whether to transmit or stop power based on the discrimination result by the discrimination circuit 34, and transmits a control signal instructing the transmission or stop of power to the power supply control unit 14. Alternatively, the present invention can be configured so that the signal transmission unit 16 transmits a signal of a waveform acquired by the electrocardiogram signal acquisition unit 6 to the power supply control unit 14, and the power supply control unit 14 discriminates which waveform the received waveform signal corresponds to, and determines whether to transmit or stop power.

[0060] The present invention can also be configured so that after the transmission of power is stopped in step S11, the transmission of power from the power supply unit 12 to the power supply unit 10 is intermittently resumed and a signal of the potential difference between the positive electrode 4b and the negative electrode 4a is acquired. This makes it possible to continue monitoring the water level in the bathtub body 2 or a malfunction of the electrocardiogram signal acquisition unit 6, etc. In this way, in the bathtub apparatus 1 of this embodiment, when the electrocardiogram signal acquisition unit 6 detects that the potential difference between the positive electrode 4b and the negative electrode 4a is in an undefined state (a state in which an "undefined potential signal" is acquired), the power supply control unit 14 at least temporarily stops the transmission of power from the power supply unit 12 to the power supply unit 10.

[0061] 9, if the signal waveform of the potential difference between the positive electrode 4b and the negative electrode 4a acquired by the electrocardiogram signal acquisition unit 6 is a waveform of a "person taking a bath" or a "person not taking a bath" signal, the process proceeds to step S6. In this case, the water level in the bathtub body 2 is determined to be higher than the height at which the positive electrode 4b and the negative electrode 4a are provided, and a signal indicating this is sent from the signal transmission unit 16 to the power supply control unit 14. As a result, in step S6, the power supply control unit 14 continues to transmit power from the power supply unit 12 to the power supply unit 10.

[0062] Next, in step S7, it is determined whether or not a person is bathing in the bathtub body 2. That is, if the signal waveform of the potential difference between the positive electrode 4b and the negative electrode 4a is determined by the discrimination circuit 34 to be the waveform of the "person present bathing signal", it is determined that a person is bathing in the bathtub body 2, and the process proceeds to step S8. On the other hand, if the signal waveform of the potential difference is determined to be the waveform of the "no person present bathing signal", it is determined that a person is not bathing in the bathtub body 2, and the process returns to step S6. Therefore, when there is no person bathing in the bathtub body 2, the process of steps S6 → S7 → S6 is repeated, and the transmission of power from the power supply unit 12 to the power supply unit 10 continues. In this way, when hot water is stored in the bathtub body 2, but the electrocardiogram signal acquisition unit 6 detects that there is no person bathing in the bathtub body 2, the power supply control unit 14 continues the transmission of power from the power supply unit 12 to the power supply unit 10.

[0063] Next, when a bather enters the bathtub body 2, the process in the flowchart proceeds from step S7 to step S8. Furthermore, in step S8, it is determined whether or not an electrocardiogram signal of the bather has been detected (whether or not the waveform of a "person taking a bath signal" has been detected). If an electrocardiogram signal has been detected, the process proceeds to step S9, where the transmission of power from the power supply unit 12 to the power supply unit 10 continues, and the process in the flowchart returns from step S9 to step S8. Therefore, when a person taking a bath is present in the bathtub main body 2, the process of steps S8 → S9 → S8 is repeated, and the transmission of power from the power supply unit 12 to the power supply unit 10 continues. In this way, when hot water is stored in the bathtub main body 2 and the electrocardiogram signal acquisition unit 6 has detected that a person is present in the bathtub main body 2, the power supply control unit 14 continues the transmission of power from the power supply unit 12 to the power supply unit 10.

[0064] Next, if it is determined in step S8 that the bather's electrocardiogram signal has not been detected, the process in the flowchart proceeds from step S8 to step S12. In step S12, it is determined whether or not hot water is stored in the bathtub body 2. That is, it is determined whether or not the signal waveform of the potential difference between the positive electrode 4b and the negative electrode 4a is the waveform of a "no-bather signal." If it is determined that the waveform is the "no-bather signal," it is considered that the bather has left the bathtub body 2, and the process in the flowchart returns from step S12 to step S6, and thereafter, the process of steps S6 → S7 → S6 is repeated.

[0065] On the other hand, if it is determined in step S12 that no hot or cold water is stored in the bathtub body 2, the process proceeds to step S13. That is, if the signal waveform of the potential difference between the positive electrode 4b and the negative electrode 4a is the waveform of an "undefined potential signal," the process in the flowchart proceeds from step S12 to step S13. In this case, the state has shifted from one in which a bather is present in the bathtub body 2 (a state in which the processes of steps S8 → S9 → S8 are repeated) to one in which no hot or cold water is stored in the bathtub body 2 (steps S8 → S12 → S13), and there is a high possibility that an abnormality has occurred in the electrocardiogram signal acquisition unit 6, etc.

[0066] Therefore, in step S13, it is determined that an abnormality has occurred, and the electrocardiogram signal acquisition unit 6 sends a signal to the remote control 6a in the bathroom R and a remote control (not shown) outside the bathroom R, and displays on the remote control that an abnormality has occurred to notify the user. Furthermore, in step S14, the signal transmitting unit 16 sends a signal to the power supply control unit 14 to stop the transmission of power from the power supply unit 12 to the power supply unit 10, and one round of the processing in the flowchart shown in FIG. 9 is completed.

[0067] In this way, when the electrocardiogram signal acquiring unit 6 detects the presence of a bather in the bathtub body 2 ("person present bathing signal") and the potential difference between the positive electrode 4b and the negative electrode 4a changes to an uncertain state ("undefined potential signal"), the power supply control unit 14 stops transmitting power to the power supply unit 10. This makes it possible to avoid supplying power to the electrocardiogram signal acquiring unit 6 in a faulty state, and reliably prevents accidents from occurring.

[0068] According to the bathtub apparatus 1 of the embodiment of the present invention, the power supply unit 12 supplies power to the power supply unit 10 via the insulating transformer 13, and the insulating transformer 13 is equipped with a contact prevention plate 13d, so that even if the insulation in the insulating transformer 13 is broken, the current supplied from the commercial power source flows to the earth via the contact prevention plate 13d, thereby making safety extremely high. As a result, in the bathtub apparatus 1 equipped with an electrocardiogram signal detection function, the probability of occurrence of a breakdown that leads to a serious accident can be brought as close to zero as possible.

[0069] Furthermore, according to the bathtub apparatus 1 of this embodiment, a signal based on the potential difference between the positive electrode 4b and the negative electrode 4a is sent to the power supply control unit 14, and the transmission of power from the power supply unit 12 to the power supply unit 10 is continued or stopped based on the sent signal. Therefore, if an abnormality occurs in the operation of the bathtub apparatus 1, the transmission of power to the power supply unit 10 can be stopped early, further reducing the probability of an accident caused by a malfunction. Furthermore, since the transmission of power is continued or stopped based on a signal detected by the positive electrode 4b and the negative electrode 4a provided on the bathtub body to detect an electrocardiogram signal, the occurrence of an abnormality can be detected without providing a special sensor.

[0070] Furthermore, according to the bathtub apparatus 1 of this embodiment, when an uncertain potential signal is detected by the electrocardiogram signal acquisition unit 6, the transmission of power from the power supply unit 12 to the power supply unit 10 is at least temporarily stopped. This makes it possible to prevent power from being transmitted to the power supply unit 10 when there is an abnormality in the bathtub apparatus 1 or when there is not enough hot or cold water stored in the bathtub main body 2, further reducing the probability of an accident occurring and avoiding the transmission of unnecessary power.

[0071] Furthermore, according to the bathtub apparatus 1 of this embodiment, when hot and cold water is stored in the bathtub body 2, but it is detected that no bather is in the bathtub body 2, the power supply unit 12 continues to transmit power to the power supply unit 10. Therefore, the electrocardiogram signal acquisition unit 6 operates normally, and can immediately start acquiring electrocardiogram signals when a bather enters the bathtub body 2.

[0072] Furthermore, according to the bathtub apparatus 1 of this embodiment, when hot and cold water is stored in the bathtub main body 2 and it is detected that a bather is in the bathtub main body 2, the transmission of power from the power supply unit 12 continues. As a result, an electrocardiogram signal can be safely acquired by a normally operating bathtub apparatus 1, which can be used to provide information about bathing to the bather or to monitor the bather.

[0073] Furthermore, according to the bathtub apparatus 1 of this embodiment, when the potential difference between the positive electrode 4b and the negative electrode 4a changes from a state in which an electrocardiogram signal is being detected to an indefinite state, the transmission of power to the power supply unit 10 is stopped, so that an abnormality in the bathtub apparatus 1 can be quickly detected and the transmission of power can be stopped. This further reduces the probability of an accident occurring and prevents the transmission of unnecessary power.

[0074] Although the preferred embodiment of the present invention has been described above, various modifications can be made to the above-described embodiment. [Explanation of symbols]

[0075] 1 Bathtub equipment 2 Bathtub body 4a negative electrode 4b Positive electrode 4c reference electrode 6. ECG signal acquisition unit 6a Remote Control 8. Water discharge device 10 Power supply section 10a front rectifier circuit 10b Pulse generation circuit 10c transformer 10d Post-stage rectifier circuit 12 Power supply section 12a Earth leakage circuit breaker 13 Isolation transformer 13a Primary winding 13b Secondary Winding 13c Core 13d Contact prevention plate 14 Power supply control unit 16 Signal transmitter 18 Commercial power supply 26 Differential Amplifier Circuit 28 Filter Circuit 30 Amplification circuit 32 A / D converter 34 Discrimination circuit 36a Recording Section 36b Display section 36c Heart Rate Converter

Claims

1. A bathtub device equipped with an electrocardiogram signal detection function, A bathtub body for storing hot and cold water; a positive electrode and a negative electrode provided in the bathtub body for detecting an electrocardiogram signal of a person bathing in the bathtub body via hot and cold water stored in the bathtub body; an electrocardiogram signal acquisition unit that acquires an electrocardiogram signal of the bather based on the potential difference between the positive electrode and the negative electrode; a power supply unit for supplying power to the electrocardiogram signal acquisition unit; a power supply unit connected to a commercial power source and supplying power to the power supply unit; a power supply control unit that controls supply and stop of power from the power supply unit to the power supply unit, A bathtub apparatus characterized in that the power supply unit supplies power to the power supply unit via an isolation transformer, and the isolation transformer is equipped with a contact prevention plate.

2. The bathtub apparatus of claim 1, further comprising a signal transmitting unit that transmits a signal to the power supply control unit, the signal transmitting unit transmitting a signal based on the potential difference between the positive electrode and the negative electrode acquired by the electrocardiogram signal acquiring unit to the power supply control unit, and the power supply control unit continuing or stopping the transmission of power from the power supply unit to the power supply unit based on the transmitted signal.

3. The bathtub apparatus according to claim 2 , wherein the power supply control unit at least temporarily stops the transmission of power from the power supply unit to the power supply unit when an uncertain potential signal is detected by the electrocardiogram signal acquisition unit.

4. The bathtub apparatus of claim 2, wherein the power supply control unit continues transmitting power from the power supply unit to the power supply unit when hot water is stored in the bathtub body but the electrocardiogram signal acquisition unit detects that no one is bathing in the bathtub body.

5. The bathtub apparatus of claim 2, wherein the power supply control unit continues to transmit power from the power supply unit to the power supply unit when hot water is stored in the bathtub body and the electrocardiogram signal acquisition unit detects that a bather is present in the bathtub body.

6. The bathtub apparatus of claim 2, wherein the power supply control unit stops transmitting power to the power supply unit when a state changes from one in which the presence of a bather is detected in the bathtub body to one in which an uncertain potential signal is detected by the electrocardiogram signal acquisition unit.

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